Method of preventing the formation of gumlike products in oils



y 30, 1940- A. c. G. EGERTON 2209,646

' METHOD OF PREVENTING THE FORMATION OF GUMLIKE PRODUCTS IN OILS Filed June 29, 1958 TANK CONTAINING GUM-INHI ITOR COM U ION C AMBER Patented July 30, 1940 4 UNITED STATES METHOD OF PREVENTING THE FORMATION I F GUMImE PRODUCTS OILS Alfred Charles Glyn Egerton, London, England Application June 29, 1938, Serial No. 216,595 In Great Britain m 2, 193':

16 Claims.

This invention relates to a method of preventing the formation of gumlike products in oils which are subjected to an atmosphere containing oxides of nitrogen.

5 It was hitherto believed that the formation of gummy matter in oils was due to the oxidationof the oil leading directly to the production of gummy oxidation products. It has now been found, however, that the formation of gumlike products in an oil used in an engine operating at or near the detonation point is greater than when the engine is not operating under de tonating conditions (see Egerton, Smith 8: Ubbelohde, Royal Society of London Philosophical l6 Transactions, 1935, vol. 234, page 433). In an engine operating under detonating conditions it was also shown, in the above publication, that the amounts of nitrogen oxides formed in the combustion chamber were abnormal.

It has now been found that the oxide of nitrogen which has the greatest efiect in promoting the formation of gums is nitrogen peroxide.

It is an object of this invention to minimise the effect of the nitrogen peroxide on the oil by the addition thereto of a nitrogen oxide inhibitor which acts either by stopping or reducing the catalytic action of nitrogen peroxide or by absorbing nitrogen peroxide and converting it into a harmless compound.

A number of experiments have shown that when oil is maintained at a temperature of-218 C. and air containing nitrogen peroxide in a proportion of about 2 parts in 10 parts of air, the amount of gum formed is increased up to about 5 ten times the amount formed when air alone is blown through the oil. These same experiments have shown that the presence of nitric oxidein the air does not increase the amount of gum formed as compared with the amount formed when air alone is used.

According to this invention a method of preventing the formation of gumlike products in oil subjected to an atmosphere containing oxides of nitrogen consists in introducing into said oil or said atmosphere 2. small proportion of a ferric compound. That is to say, the small proportion of the ferric compound may be introduced directly into and dispersed in said oil; or, instead, said ferric compound may be introduced into said atmosphere to which the oil is subjected by introduction, either separately from or in dispersion in the motor fuel,. into the combustion chamber of the internal combustion engine with which said oil is used. The last mentioned practice, the introduction of the ferric compound into the combustion chamber of the engine in dispersion in the engine fuel, presents the advantage of the use of the ferric inhibitors of the present invention commercially as additions to the gasoline or other like fuel of an internal combustion engine for the purpose of minimizing the effect of nitrogen peroxide on the lubricating oil under operating conditions of the engine.

Oxidation tests which have been carried out have shown that the addition of small quantities 10 of ferric oxide markedly reduce the amount of um formed in an oil which is heated in the presence of nitrogen peroxide, and it is therefore a feature of the invention that ferric oxide is added tothe oil. 15

The use of ferric salts of fatty acids has been found very considerably to reduce the formation of gum; ferric ricinoleate has been tested and found to be particularly successful.

The drawing shows a diagrammatic arrangen ment whereby the gum inhibitor may be introduced into the combustion chamber of an internal combustion engine and shows a tank of the gum inhibitor connected by a supply line to the engine communicating with the combustion chamber through which supply line the gum inhibitor is introduced into the combustion chamher.

I claim:

1. A lubricant comprising a lubricating oil adapted for use in an internal combustion engine and having dispersed therein a small proportion of an inorganic ferric compound adapted to retard or inhibit gum formation in said oil.'

2. A lubricant comprising a lubricating oil adapted for use in an internal combustion engine 35 and having dispersed therein between 0.5 and 5% byweight of an inorganic ferric compound adapted to retard or inhibit gum formation in said oil.

3. A lubricant comprising a lubricating oil having dispersed therein a small proportion of ferric oxide.

4. A lubricating oil adapted for use in an internal combustion engine and having dispersed therein between .05 and 5% by weight of ferric ricinoleate adapted to retard or inhibit gum formation in said oil.

5. A method of preventing the formation of gumlike products in lubricating oils subjected to 50 the action of an atmosphere containing nitrogen peroxide in an internal combustion engine which consists in dispersing in the engine fuel a small proportion of a ferric salt of a fatty acid capable of functioning as a retarder or inhibitor of gum formation in said oils subjected to said atmosphere.

6. A method of preventing the formation of gumlike products in lubricating oils subjected to the action of an atmosphere containing nitrogen peroxide in an internal combustion engine which consists in dispersing in the engine fuel a small proportion of ferric ricinoleate.

7. A method of preventing the formation of gumlike products in lubricating oils subjected to the action of an atmosphere containing nitrogen peroxide in an internal combustion engine which consists in introducing into the lubricating oil a nitrogen peroxide inhibitor of the class consisting of inorganic ferric compound, organic ferric compounds and ferric salts of fatty acids.

8. A method of preventing the formation of gumlike products in lubricating oils subjected to the action of an atmosphere containing nitrogen peroxide in an internal combustion engine which consists in introducing into the lubricating oil a nitrogen peroxide inhibitor comprising ferric oxide.

9. A method of preventing the formation of gumlike products in lubricating oils subjected to the action of an atmosphere containing nitrogen peroxide in an internal combustion engine which consists in introducing into the lubricating oil a nitrogen peroxide inhibitor comprising ferric ricinoleate.

10. A method of preventing the formation of gumlike products in lubricating oils subjected to the action of an atmosphere containing nitrogen peroxide in an internal combustion engine which consists in introducing into the lubricating oil a nitrogen peroxide inhibitor comprising ferric ricinoleate in the proportion of between .05 and 5% by weight of the oil.

11. A motor fuel for an internal combustion engine using lubricating oil and subjecting said oil to an atmosphere of nitrogen peroxide in the engine tending to cause formation of gumlike products in said oil, said motor fuel comprising gasoline or the like combustible hydrocarbon having a small proportion of ferric oxide dispersed therein.

12. A motor fuel for an internal combustion engine using lubricating oil and subjecting said oil to an atmosphere of nitrogen peroxide in the engine tending to cause formation of gumlike products in said oil, said motor fuel having a small proportion of ferric ricinoleate dispersed therein.

13. A method of preventing the formation of gumlike products in lubricating oils subjected to the action of an atmosphere of nitrogen peroxide in an internal combustion engine tending to cause such formation, which method comprises introducing into the combustion chamber of the internal combustion engine a small proportion of a ferric compound capable of functioning to retard or inhibit action of nitrogen peroxide in formation of gumlike products in said oils subjected to said atmosphere.

14. A method of preventing the formation of gumlike products in lubricating oils subjected to theaction of an atmosphere containing nitrogen peroxide in an internal combustion engine tending to cause such formation, which method consists in dispersing in the engine fuel a small proportion of a ferric compound capable of functioning to retard or inhibit action of nitrogen peroxide in formation of gumlike products in said oils subjected to said atmosphere.

15. A method of preventing the formation of gumlike products in lubricating oils subjected to the action of an atmosphere containing nitrogen peroxide in an internal combustion engine which consists in introducing into the combustion chamber of the internal combustion engine a nitrogen peroxide inhibitor of the class consisting of inorganic ferric compounds, organic ferric compounds and ferric salts of fatty acids.

16. A method of preventing the formation of gumlike products in lubricating oils subjected to the action of an atmosphere containing nitrogen peroxide in an internal combustion engine which consists in introducing into the combustion chamber of the internal combustion engine a small proportion of an inorganic ferric compound.

ALFRED CHARLES GLYN EGERTON. 

